Photographic emulsions containing 5-pyrazolone coupler compounds



limited grates i atent O PHOTOGRAPHIC EMULSIONS CONTAINING S-PYRAZOLONE COUPLER COMPOUNDS George Feniak, Anthony Loria, and Warren A. Reckhow, Rochester, N.Y., assignors to Eastman Kodak Conn pany, Rochester, N.Y., a corporation of New Jersey No Drawing. Application September 6, 1956 Serial No. 608,210

8 Claims. (Cl. 96-100) This invention relates to photography and particularly to compounds which form dyes on coupling with the developing agent to produce colored images.

It is known that colored photographic images may be formed by using a developer which produces a colored image on development. The colored compound thus formed is deposited adjacent the silver grains of the silver image during development. It is also known that a colored image may be formed by adding to said developer solution or by incorporating in the silver halide emulsion before or after exposure a compound which couples during development with the oxidation product of the developing agent and which forms a colored compound which is likewise deposited adjacent the silver grains of the silver image during development. Such a compound which is employed in conjunction with a developing agent for the silver and which couples with the oxidation product of the developing agent during development is referred to herein as a coupling compound or coupler.

The use of various pyrazolone derivatives as couplers for the production of the magenta image in three-color photography is well known and the use of 1-phenyl-3- acylamino-S-pyrazolones for this purpose is described in Porter and Weissberger U.S. Patent 2,369,489, and Loria, Weissberger and Vittum U.S. Patent 2,600,788, granted June 17, 1952. One of the disadvantages of these couplers lies in the fact that when the couplers are incorporated into sensitive emulsion layers the residual coupler which remains after formation of the dye image is not as stable to heat and light as desired. Other couplers such as the 3-alkyl-5-pyrazolone couplers unsubstituted in the 1-position of the pyrazolone nucleus or containing a phenyl group in the 1-position produce with color developing agents magenta dyes having undesirable secondary light absorptions.

One object of our invention is to provide a new class of couplers for color photography. A further object is to provide couplers which are stable to light and heat when incorporated into an emulsion layer. A further object is to provide couplers which yield dyes whose secondary light absorptions are at a minimum.

These objects are accomplished by developing an exposed silver halide emulsion layer with a primary aromatic amino silver halide developing agent in the presence of a 1-phenyl-3-alkyl-5-pyrazolone coupler having at least two halogen substituents on the l-phenyl radical and from 11 to 17 carbon atoms in the alkyl radical. Presumably the improvement in light absorption characteristics (low secondary absorptions of dyes made from the couplers) can be attributed to the presence of the halogenated phenyl group in the 1-position of the pyrazolone nucleus inasmuch as the simple 3-alkyl-5- pyrazolones do not possess this desirable characteristic. The reason for improvement for stability in the halogenated 1phenyl-3-alkyl-5-pyrazolone couplers of the invention compared to comparable halogenated 1-phenyl-3- acylanfido-S-pyrazolone couplers is not apparent.

ice

The coupler compounds of the invention have the following general formula:

N=C-R O X II o where X is a halogen atom such as chlorine or bromine, n is a positive integer at least as great as 2 and R is an alkyl group of from 11 to 17 carbon atoms.

The following compounds illustrate the coupler compounds which can be used in our invention:

1-(2,4,6-trlehloropheny1)-3-pentadecy1-5-pyrazolone N=C-CuH2s-n 0 1- (2,4,6-trlchloropheny1) -3-unde cyI-5-pyrazolone O 1-(2,4,6-tr1ch1orophenyl)-S-heptadecyl-E-pyrazolone C 01 ll 0 1- (2,4,5-tr1chlorophenyl) -3-pentadecyl-5-pyrazo1one 1- (2,4,5-trichlorophenyl) -3-heptadecyl-fi-pyrazolone N=C--C 5Ha -11 1- (2,4-dlch1orophenyl) -3-pentadecyl-5-pyrazolone G1 /N=CC17H3rn (J-CH2 01 ll 0 1- 2,5-dlchloropheny1) -3-heptadecyl5-pyra.zolone 1 2,6-dlchlorophenyl -3-heptadecyl-5-pyruzolone The above couplers are prepared as follows: 1 (2,4,6-trichlorophenyI)-3-pentadecyl-5-pyrazo l0ne.-- 2,4,o-trichlorophenylhydrazine 7.3 g. (prepared as given in Loria et al., U.S. Patent 2,600,788, June 17, 1952) and ethyl-3-ketooctadecanoate 11.3 g. (prepared as given by B. Helferich and H. Coster Ber. 56B 2088-94 (1923) Analysis Calc. for Found CziHasClaNgO Percent Percent 1-(2,4,6-trichl0r0phenyl) 3 -.undecyFS-pyrazolone- This coupler was prepared in the same manner as the above .coupler except using ethyl-3-ketotetradecanoate (B.P. 1l5-120/1 mm.) (M. Viscontini and N. Merckling Helv. Chim. .Acta 35 2280-82 (1952)) instead of ethyl-3-ketooctadecanoate. The product was crystallized from absolute ethyl alcohol using activated charcoal. A white powder was obtained, M.P. 76-79 C.

Analysis Calc. for Found CM nCIaNaO Percent Percent 1 (2,4,6-trichlorophenyD-3-heptadecyl-S-pyrazolona- This coupler was prepared in the same manner except using ethyl-3-ketoeicosancate (M.P. 44-45) instead of ethyl-3-ketooctadecanoate. The product was crystallized from methyl alcohol M.P. 74-75 C.

Analysis Gale. for Found ze anGlaO Percent Percent C 62. 2 61. 9 H 7. 8 7. 6 C 21. 1 21. 0 N 5. 5 6. 5

The other couplers illustrating the invention were prepared in the same manner using'the appropriate halogenated phenyl hydrazine and 3-keto-ester and were found to have the following physical properties:

1 (2,4,5-uichlorophenyl)-3-pentadecyl-5-pyrazolone- M.P. 107-1085 crystallized from absolute .ethyl alcohol.

1 (2,4,5-trichlorophenyl) -3-heptadecyl-5-pyrazolone- M.P. 94-96 crystallized several times from absolute ethyl alcohol.

1 (2,4-dichlorophenyl)-3-pentadecyl 5 pyrazolone- M.P. 100-101 C. crystallized from absolute ethyl alcohol.

1-(2,51dichlorophenyl)-3-heptadecyl 5 pyrazolone- M.P. 94-96 C. crystallized from absolute ethyl alcohol.

l-(2,6-dichlorophenyl)-3-l1eptadecyl S pyrazolone- M.P. 94-96 C. crystallized from absolute ethyl alcohol.

The coupler compounds of the invention are primarily of use in silver halide emulsion layers and can be dispersed in an emulsion layer such as a gelatino-silver halide emulsion layer by means of coupler solvents including cellulose'esters, natural and synthetic resins and "organic crystalloidal materials having a boiling point 'aboveaboutl'76" C., .as described in the Marines et a1.

'U'ZSJ'Patent12304340,. grantedIDecember 15, 1942, and

thef'le'lley etal. US. Patent 2,322,027, .grantedilune 15,

the particular coupler, the silver halide content of the emulsion layer, the particular process in which the emulsion is to be used and other factors well known in the art of emulsion making. V

The aromatic amino developing agents used with the coupler compounds of our invention include the mono-, diand tri-amino aryl compounds and their derivatives formed by substitution in the amino group as well as in the ring such as alkyl phenylene diamines and alkyl toluene diamines. These compounds are usually used in the salt form such as the hydrochloride or the sulfate which are more stable than the amines themselves. Suitable compounds are diethyl-p-phenylene diamine hydrochloride, monoethyl-p-phenyleue diamine hydrochloride, dimethyl-p-phenylene diamine hydrochloride, dimethylp-phenylene diamine sulfate and Z-amino-S-diethyl amino toluene sulfate. The p-amino phenols and their substitution products may also be used where the amino group is unsubstitutedL; All of these compounds have an unsubstituted amino group which enables the oxidation Grams 2-amino-5-diethylaminotoluene hydrochloride 32 Sodium sulfite (anhydrous) 2 Sodium carbonate (anhydrous) 20 Potassium bromide 2 Water to 1 liter.

The colloid vehicle of the silver halide emulsion containing the couplers of the invention may be gelatin-or other hydrophilic carrier for silver halide such as collodion, organic esters of cellulose or synthetic resins; The support for the emulsion may be a transparent material such as glass, cellulose ester or a non-transparent reflecting material such as paper or an opaque cellulose ester. The emulsion may be coated as a single layer on the support or as superposed layers on one or both'sides of the support. The superposed layers may be differentially sensitized to form natural color photographic images in the Well-known manner. For example, in a multilayer material sensitized to red, green and-*blue light, respectively, our couplers would ordinarily beused in the green-sensitive emulsion layer to form the magenta image.

The examples and compounds set forth herein are illustrative only and it is to be understood that our invention is to be taken as limited only by the scope of the appended claims.

What we claim is:

1. A light-sensitive photographic silver halide emulsion layer containing a member of the class consisting of a 1-(dichlorphenyl-)-3-alkyl-5-pyrazolone and a l-(trichlorophenyl)-3-alkyl-5-pyrazolone, the alkyl radical of which contains from ll-to 17 carbon atoms.

2. A light-sensitive photographic silver halide emulsion layer containing a l-(trichlorophenyl)-3-alkyl-5-pyraz- 'olone coupler compound, the alkyl radical of which 6. A light-sonsitive photographic silver halide emulsion References Cited in the file of this patent Isa-511,31; aggllggmng l-(2,4,6-tr1chlorophenyl)-3-heptadecy1- UNITED STATES PATENTS 7. A light-sensitive photographic silver halide emulsion 2,354,552 Schneider et y 25, 1944 lgyer Containing 1-(2,4,5-trich1orophenyl)-3-pentadecyl- 5 2,437,063 Zeb et a1. Mar. 2, 1948 5-pyrazolone. 1 2,600,788 Loria et al. June 17, 1952 8. A light-sensitive photographic silver halide emulsion 2,706,683 Sawdey Apr. 19, 1955 layer containing 1-(2,4,5-trichlorophenyl)-3-heptadecyl- 5-pyrazolone. 

1. A LIGHT-SENSITIVE PHOTOGRAPHIC SILVER HALIDE EMULSION LAYER CONTAINING A MEMBER OF THE CLASS CONSISTING OF A 1-(DICHLORPHENYL-)-3-ALKYL-5-PYRAZOLONE AND A 1-(TRICHLOROPHENYL)-3-ALKYL-5-PYRAZOLONE, THE ALKYL RADICAL OF WHICH CONTAINS FROM 11 TO 17 CARBON ATOMS. 